1. Field of the Invention
This invention relates to a variable capacity swash plate compressor in which the amount of stroke of each piston changes according to an inclination of the swash plate whereby the delivery quantity of the compressor is changed.
2. Description of the Prior Art
A conventional variable capacity swash plate compressor includes a thrust flange rigidly fitted on a drive shaft, for rotation in unison with the drive shaft, a swash plate which is tiltably and rotatably mounted on the drive shaft and connected to the thrust flange via a linkage, for rotation in unison with the thrust flange, and a plurality of pistons each of which is connected to the swash plate via a pair of hemispherical shoes performing relative rotation on sliding surfaces of the swash plate with respect to the circumference of the swash plate, and reciprocates within a cylinder bore as the swash plate rotates.
The pair of shoes are arranged on an outer peripheral portion of the swash plate in a manner sandwiching the same, in a state slidably held at one end portion of the piston.
The swash plate is received in a crankcase. The inclination of the swash plate varies with pressure within the crankcase, whereby the amount of stroke of the piston is changed.
Torque of an engine installed on an automotive vehicle is transmitted to the drive shaft. Torque of the drive shaft Is transmitted from the thrust flange to the swash plate via the linkage to cause rotation of the swash plate.
As the swash plate rotates, the pair of shoes perform relative rotation on the front-side and rear-side sliding surfaces of the swash plate, respectively, with respect to the circumference of the swash plate, whereby torque transmitted from the swash plate to converted into reciprocating motion of the piston. As the piston reciprocates within the cylinder bore, the volume of a compression chamber within the cylinder bore changes, whereby suction, compression and delivery of refrigerant gas are carried out sequentially, and high-pressure refrigerant gas is discharged in an amount or volume corresponding to an inclination of the swash plate.
In the conventional compressor, however, since the hemispherical shoes are constructed to form an imaginary sphere with the outer peripheral portion of the swash plate interposed therebetween, each of the shoes is required to be thin. Therefore, the shoes are not easily held at the end of the piston, which makes it difficult to assemble the shoes and the piston with the swash plate whether manually or automatically.
Further, if a compressor has as many as five to seven pistons, space between adjacent ones of the pistons of the compressor becomes so small that it is difficult to even put hands therebetween, which also makes it difficult to assemble the shoes and the piston with the swash plate by manual work.